National Park Service

Southwest Alaska Network (SWAN)

Freshwater Flow Systems

Kaguyak Crater Lake, Katmai National Park and Preserve
Kaguyak Crater Lake, Katmai National Park and Preserve

Resource Briefs

Protocol Documents

Monitoring Reports

Published Articles

Links to Partner Websites

For more information contact: Krista Bartz

Justification and Issues

Network parks contain some of the largest and most "pristine" freshwater resources in the national park system. These include the two large lakes, Naknek Lake and Lake Clark, numerous multi-lake systems, and thousands of miles of rivers, including five designated "Wild Rivers" — and largely unexploited resident lake fish populations. Aquatic systems in the interior of Katmai and Lake Clark NP&Ps are so extensive that they form the physical template upon which nearly all biological systems are organized.

In establishing these park units, Congress recognized the importance of clean water, with a specific reference to protecting and maintaining rivers and/or lakes in their natural state in the enabling legislation for ALAG, ANIA, KATM, and LACL. Legislation for KEFJ mentions the Harding Icefield — a major source of fresh water for this park and the adjacent coastal zone.

A SWAN technician prepares to measure discharge with an Acoustic Doppler Current Profiler at the Kijik Lake outlet in Lake Clark National Park and Preserve
A SWAN technician prepares to measure discharge with an Acoustic Doppler Current Profiler at the Kijik Lake outlet in Lake Clark National Park and Preserve

Resource Brief — Surface Hydrology

Protocol Documents

Monitoring Reports

Links to Partner Websites

For more information contact: Krista Bartz

Importance/Issues

In establishing SWAN parks, Congress recognized the importance of clean water, with a specific reference to protecting and maintaining rivers and lakes in their natural state in the enabling legislation. Climate warming is decreasing glacial coverage in SWAN, shortening the length of ice cover on lakes, and increasing evaporation from water and land surfaces. This appears to be changing surface hydrology which, in turn, will also influence water chemistry, availability and character of aquatic habitats to fish and wildlife populations, and recreational access and opportunities.

Objectives and Monitoring Approach

  • Monitor maximum and minimum annual daily flow, maximum and minimum annual 3-d or 7-d duration flow, and total annual water yield in selected SWAN river systems
  • Monitor annual trends in the timing and magnitude (average, maximum, minimum) of lake levels in selected SWAN flow systems

Stream flow will be estimated for targeted streams using Acoustic Doppler Current Profile (ADCP) and lake level measurements. ADCP technology is well suited for large, fast flowing rivers, such as the outlet streams for Tier 1 lakes. SWAN staff are currently developing a methodology for estimating stream flow in the outlet streams of Lake Clark and Naknek Lake. These locations provide opportunities to collect watershed-level information on flow systems that characterize and encompass a significant portion of SWAN park land. If proven feasible, SWAN or park staff would record lake levels, stream profiles and ADCP discharge measurements on a 2-5 yr basis.

Current and Future Work efforts

Absolute water level recorders and recording barometers are installed seasonally at sites located at the outlets to Lake Brooks and Naknek Lake in Katmai. These instruments are used to characterize the open-water hydrographs of Tier 1 systems in Katmai. ADCP measurements are taken at these sites to compare against and potentially refine developed rating curves. Water level on Lake Clark is recorded via tape-down measurements in Hardenburg Bay seasonally, and ADCP measurements are taken at Lake Clark’s outlet stream. Additionally, absolute water level recorders are located on submerged temperature monitoring equipment in both Lake Clark and Katmai to capture over-winter lake levels.

Lake chemistry sampling with a multiparameter sonde on Upper Twin Lake, Lake Clark National Park and Preserve
Lake chemistry sampling with a multiparameter sonde on Upper Twin Lake, Lake Clark National Park and Preserve

Resource Brief — Water Quality

Protocol Documents

Monitoring Reports

Published Articles

Links to Partner Websites

For more information contact: Krista Bartz

Importance/Issues

SWAN parks contain some of the largest and most pristine freshwater resources in the national park system. These include two large lakes, Naknek Lake and Lake Clark, numerous multi-lake systems, and thousands of miles of rivers, including five designated “Wild Rivers”. Lakes and streams comprise interconnected flow systems within the broader landscape. They are interactive with their adjacent environments, integrative of the biophysical processes occurring there, and thereby sensitive to local climate (changes in precipitation, glacial retreat or advance), natural disturbance events (fire, landslides, volcanic eruptions) and land-use changes in and adjacent to parks. Despite their remoteness, freshwater resources of SWAN parks are subject to several types of influence affecting their function through time. Humans affect SWAN freshwater environments by altering the climate, introducing contaminants, and through land use. Water quality, especially dissolved oxygen, pH, and temperature, is not only important for maintenance of biological life, but can control or alter biogeochemical cycling as well as the toxicity of some elements.

Objectives

  • Observe annual and interannual variability in maximum, minimum, and average temperature, pH, dissolved oxygen, specific conductance and turbidity in selected SWAN flow systems
  • Quantify midsummer lake profiles of temperature, specific conductance, pH, dissolved oxygen, and turbidity on an annual basis for high-priority lake systems and less frequently for other SWAN lakes
  • Estimate nutrient and chlorophyll concentrations on an annual basis in high-priority lake systems and less frequently for other SWAN lakes
  • Monitor dissolved major ions, trace elements, and alkalinity on an annual basis for high-priority lake systems and less frequently for other SWAN lakes

Monitoring Approach

SWAN park waters are relatively pristine, with no lakes or rivers listed as impaired pursuant to section 303(d) of the Clean Water Act. Most lakes and streams are oligotrophic, with low biological activity, low nutrient loads and low to moderate acid buffering capacity. Because water quality in SWAN parks is relatively pristine, monitoring focuses on documenting natural variability within park systems and changes due to affects such as climate change. Highest priority, or Tier 1 lakes (Naknek Lake and Lake Brooks in Katmai and Lake Clark and Kijik Lake in Lake Clark) are not only of high management concern, but are readily accessible and are sampled on an annual basis. Tier 2 and Tier 3 flow systems (medium and low priority) lakes are less accessible than their Tier 1 counterparts; these lakes are important for expanding spatial inference to ensure trends observed at Tier 1 sites represent other flow systems in the parks. Lakes in this latter sample are stratified by lake size, water type (clear, glacial) and accessibility.

A technician holds a lake trout caught for sampling in Lake Clark National Park and Preserve
A technician holds a lake trout caught for sampling in Lake Clark National Park and Preserve

Resource Brief — Lake Fish

Protocol Documents

Monitoring Reports

Links to Partner Websites

For more information contact: Krista Bartz

Importance/Issues

Resident lake fish serve an important ecological role in SWAN parks. They represent a variety of trophic levels (omnivores, insectivores, planktivores, and piscivores) and hence reflect changes that occur in the food chain. Non-anadromous fish also provide a measure of environmental contaminants in aquatic systems. In addition, resident lake fish are relatively easy to sample and use variable habitats so they are well suited to serve as environmental indicators.

Resident fish play important recreational, economic, and subsistence roles as well. Several species, such as rainbow trout (Oncorhynchus my kiss), lake trout (Salvelinus namaycush), and Arctic grayling (Thymallus arcticus), provide excellent recreational opportunities to local, in-state, and out-of-state anglers, which may inject significant sources of income to local and state economies. Whitefish (Coregonus spp., Prosopium spp.) and northern pike (Esox lucius) are important subsistence species for local native Alaskans.

Monitoring Objectives

  • Monitor presence of key recreational, subsistence, and other native species of resident fish annually within high priority lakes.
  • Monitor potential influx of non-native fish species within high-priority lakes in KATM and LACL.

Current and Future Work Efforts

In 2011, SWAN sampled selected freshwater fish species to establish baseline contaminant concentrations to assess future trends. This sampling effort focused on two aspects of contaminant monitoring: 1) assessment of total mercury and heavy metals in lake trout, northern pike, and whitefish (Coregonus spp.), and 2) assessment of persistent organic pollutants in lake trout and slimy sculpin (Cottus cognatus). Over 200 fish were collected from anadromous and non-anadromous lakes to assess the role that Pacific salmon play in importing contaminants into SWAN lakes. For mercury and heavy metals, our primary concern is bioaccumulation in freshwater species utilized by subsistence users. By comparing heavy metal concentrations in freshwater species collected in anadromous and nonanadromous lakes, we can estimate the contribution of marine sources of mercury and other heavy metals transported into these systems by Pacific salmon. Our primary interest in persistent organic pollutants is one of ecological effects, thus we will sample ubiquitous species from different trophic levels. Results will be available in the Fall of 2013.

A salmon spawns near Katmai National Park and Preserve, Photo: K. Mueller/FWS
A salmon spawns near Katmai National Park and Preserve, Photo: K. Mueller/FWS

Resource Brief — Salmon

For More Information

For more information contact: Krista Bartz

Importance/Issues

Pacific salmon (Oncorhynchus spp.) play a critical role in maintaining productivity of many freshwater and adjacent terrestrial systems in SWAN parks by transporting marine-derived energy and nutrients upstream, by consumption of returning spawners by terrestrial predators, and by processes related to the decomposition and redistribution of post-spawning carcasses and their nutrients (Naiman et al. 2002, Schindler et al. 2003). Adult spawners provide a crucial food resource to brown bears (Ursus arctos), an excellent recreational opportunity to anglers, and an important subsistence and cultural resource to Native Alaskans. Sockeye (Oncorhynchus nerka) is an especially important species in this regard within SWAN parks and is specifically named in the enabling legislation of LACL. Therefore, monitoring abundance and condition of sockeye salmon returning to spawn (escapement) is of paramount importance to sustain this critical species. In addition, tracking spawner distribution and number of recruits per spawner within streams and lakes across time provides a measure of habitat quality and change (Hilborn et al. 2003). Changes in timing of spawning runs may indicate climatic shifts. Freshwater residence time and condition of out-migrating juvenile salmon are used to indirectly measure productivity of natal habitats.

Monitoring Objectives

  • Devise and implement a protocol for obtaining past, present, and future data from ADF&G on spawner abundance and distribution, timing of spawning runs, and freshwater residence time of sockeye salmon from sampled systems in SWAN parks
  • Estimate long-term trends in spawner abundance, growth rates and distribution, timing of spawning runs, and freshwater residence time and body condition of sockeye salmon in SWAN parks

Current and Future Work Efforts

Coming soon

Last Updated: February 07, 2017 Contact Webmaster